REORGANIZATION:The Central Weather Bureau changed its evaluation of a string of quakes, determining that a quake on Sunday was a foreshock to Tuesday’s temblor

Firefighters head toward the quake-hit Yun Men Tsui Ti building in Hualien yesterday.

Photo: CNA

Seven people were killed and 260 injured after a magnitude 6.0 earthquake struck off the coast of Hualien County on Tuesday night, the Central Emergency Operation Center said yesterday.

The center’s data showed that four buildings in Hualien City had collapsed or tilted due to the earthquake: the Marshal Hotel (統帥飯店), the Yun Men Tsui Ti (雲門翠堤大樓) commercial and residential building and two apartment buildings on Guosheng 6th Street.

As of 9:30pm yesterday, 67 people were reported missing, 39 of whom were thought to have been in the Yun Men Tsui Ti building.

However, rescue efforts at the Yun Men Tsui Ti building have been precarious, with the building tilting ever more toward the ground amid multiple aftershocks.

A total of 31,558 households were waiting for their water supply to resume, while 186 households were left without electricity, the data showed.

About 560 people have been placed in shelters after being evacuated from their homes on Tuesday night, the data showed.

Huang Jui-tien (黃瑞添), a resident of Hualien County’s Jian Township (吉安), told the Taipei Times in a telephone interview that even though there have been aftershocks since a magnitude 5.8 earthquake on Sunday night, he felt that Tuesday’s earthquake was much bigger, because things started to shake vertically instead of horizontally.

Huang said he and his family rushed out of their home during the earthquake and returned to find that all of the bonsai plants in the house had fallen to the ground.

“We were afraid to go back to sleep again, because the aftershocks continued almost nonstop,” he said.

Most restaurants and shops in the area were closed yesterday, Huang said, adding that convenience stores had run out of hot food.

Asked what his family would do, as the aftershocks are expected to continue over the next few weeks, he said: “Well, life has to go on.”

The Ministry of National Defense has deployed 661 military personnel to assist rescue efforts.

Central Weather Bureau (CWB) data showed that Tuesday’s earthquake, which measured magnitude 6.0 on the Richter scale, occurred at 11:50pm at a depth of 10km and its epicenter was 18.3km northeast of Hualien County Hall, which is near the coast.

Seismic intensity refers to the degree of vibration felt at a location during an earthquake.

On the nation’s zero-to-seven seismic intensity scale, level 7 indicates shaking so violent that people cannot move at will.

As of 5pm yesterday, the bureau had recored 159 aftershocks since Tuesday night’s big quake.

The bureau had previously said that Sunday’s magnitude 5.8 earthquake was the main earthquake and that it expected tectonic movement to gradually cease after multiple aftershocks.

However, it changed its evaluation yesterday, saying that Tuesday’s magnitude 6.0 temblor was the main earthquake and Sunday’s was one of its 94 foreshocks.

“This seismic sequence has completely changed the way we think about earthquakes in this region,” Seismological Center Acting Director Chen Kuo-chang (陳國昌) said.

Chen confirmed that Tuesday’s earthquake was the largest in Hualien County since the bureau began conducting more precise observations of earthquakes in 1972.

The bureau said that the earthquake occurred as a result of an interaction between the Philippine Sea Plate and Eurasia Plate, with some seismologists saying that this might trigger movement of the Milun Fault, along which the damaged buildings were constructed.